Liver disease in pediatric cystic fibrosis. A review of current knowledge

Cystic fibrosis, the second most common genetic disease, is the result of a mutated channel protein, CFTR, which secretes chloride ions that fluidize secretions. Life expectancy in patients has increased in recent years thanks to improvements in treatment. However, hepatic complications are the third leading cause of death and the understanding of their pathophysiology is still poor. Biliary obstruction secondary to the presence of thick secretions is considered to lead to cirrhosis. However, ursodeoxycholic acid has not modified the natural history. Moreover, the presence of portal hypertension in the absence of cirrhosis cannot be explained. The role of CFTR as a modulator of immune tolerance has been proposed, which explains the presence of persistent portal inflammation culminating in fibrosis. The gut-liver axis would have an important role in the presentation and progression of this disease.